The prior tool rack developed by the inventor has been registered with U.S. patent application Ser. No. 11/616,856 in the United States. It includes a frame, a restriction member, and multiple locking members. The frame has multiple receiving recesses established laterally in parallel, and each receiving recess is composed of two clamp plates to hold wrenches in different sizes with parallel distance. Each clamp plate has a spring piece which biases the tool to position the tool within the receiving recesses. A restriction member is transversely slidably connected to the frame and includes multiple restriction portions which are snapped on the tools to prevent the tools from being taken out easily by unidentified force. Locking members lock up the restriction member onto the frame when the clamp plates hold tools.
However, the tool rack mentioned above still has some disadvantages:
1. The clamp plates protrude from the frame and their edges can easily be hooked by external matters due to short of cover protection. For example, they might tangle with user's sleeves or clothes, and cause inconvenience to use the tools.
2. The multiple clamp plates are densely arranged on the frame and their exposure makes the frame look awkward.
3. When wrenches are placed on the rack, the driving heads of the wrenches protrude out from the frame and may be hit by stiff matters. This may damage the driving heads of the wrenches.